Acute cholecystitis is acute inflammation of the gall-bladder wall, initiated most often by cystic-duct obstruction with secondary bacterial infection. The clinical picture evolves over hours, and recognition of its characteristic features guides early imaging, antibiotic therapy, and timely surgical intervention.

1. Right-upper-quadrain pain
   Persistent, often severe pain begins beneath the costal margin, may radiate to the right scapula or inter-scapular region, and is exacerbated by deep inspiration or movement. Pain typically lasts > 6 h and is unrelenting.
2. Murphy sign
   Inspiratory arrest elicited by palpation of the right upper quadrant during deep inspiration is a reliable physical finding; a positive Murphy sign has high diagnostic accuracy.
3. Fever and systemic response
   Low-grade pyrexia (37.5–38.5 °C) with chills is usual; higher temperatures or rigors suggest suppurative complications such as empyema or gangrene.
4. Nausea and vomiting
   Gastric stasis and vagal reflexes produce repeated retching that may transiently lessen pain but contributes to dehydration and electrolyte imbalance.
5. Tender hepatomegaly and guarding
   The gall-bladder fundus is palpable as a smooth, exquisitely tender mass; voluntary guarding progresses to board-like rigidity if peritonism develops.
6. Laboratory inflammation
   Leukocytosis with neutrophil left shift, elevated C-reactive protein, and modest rise in serum alkaline phosphatase and transaminases are characteristic; total bilirubin may be mildly elevated unless common bile-duct stones coexist.
7. Local complications
   Persistent high fever, unrelenting pain, or palpable emphysematous crepitus indicates gangrene, perforation, or emphysematous cholecystitis and mandates urgent intervention.